On 04/09/2021 00:28, Fabiano Rosas wrote:
Alexey Kardashevskiy <aik@xxxxxxxxx> writes:
At the moment the generic KVM code creates an "%pid-%fd" entry per a KVM
instance; and the PPC HV KVM creates its own at "vm%pid".
The rproblems with the PPC entries are:
1. they do not allow multiple VMs in the same process (which is extremely
rare case mostly used by syzkaller fuzzer);
2. prone to race bugs like the generic KVM code had fixed in
commit 85cd39af14f4 ("KVM: Do not leak memory for duplicate debugfs
directories").
This defines kvm_arch_create_kvm_debugfs() similar to one for vcpus.
I think kvm_arch_create_vm_debugfs is a bit mode accurate?
ah yes, it is better.
^
This defines 2 hooks in kvmppc_ops for allowing specific KVM
implementations to add necessary entries.
This makes use of already existing kvm_arch_create_vcpu_debugfs.
This removes no more used debugfs_dir pointers from PPC kvm_arch structs.
Suggested-by: Fabiano Rosas <farosas@xxxxxxxxxxxxx>
Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx>
...
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index c8f12b056968..325b388c725a 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2771,19 +2771,14 @@ static const struct file_operations debugfs_timings_ops = {
};
/* Create a debugfs directory for the vcpu */
-static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id)
+static void kvmppc_arch_create_vcpu_debugfs_hv(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry)
This could lose the 'arch' since it is already inside our code and
accessed only via ops. I see that we already have a
kvmppc_create_vcpu_debugfs that's used for some BookE processor, this
Ouch, missed kvmppc_create_vcpu_debugfs(). Good eye :)
would make:
kvmppc_create_vcpu_debugfs
kvmppc_create_vcpu_debugfs_hv
kvmppc_create_vcpu_debugfs_pr (possibly)
which perhaps is more consistent.
Or kvm_arch_vm_ioctl_hv(). I really like having "arch" in the name,
tells right away what it is about. "kvmppc" might be excessive. Thanks,
{
- char buf[16];
- struct kvm *kvm = vcpu->kvm;
-
- snprintf(buf, sizeof(buf), "vcpu%u", id);
- vcpu->arch.debugfs_dir = debugfs_create_dir(buf, kvm->arch.debugfs_dir);
- debugfs_create_file("timings", 0444, vcpu->arch.debugfs_dir, vcpu,
+ debugfs_create_file("timings", 0444, debugfs_dentry, vcpu,
&debugfs_timings_ops);
}
#else /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */
-static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id)
+static void kvmppc_arch_create_vcpu_debugfs_hv(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry)
{
}
#endif /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */
--
Alexey
